The present invention relates to lamp bases for use with lamp assemblies, and more particularly to a lamp base for use with a lamp having dual legs.
A variety of gas discharge lamp assemblies are available in a dual-leg construction, including both UV and fluorescent lamps. A dual-leg construction is relatively compact and therefore provides a number of benefits over conventional single tube lamp assemblies. A conventional dual-leg lamp includes a pair of side-by-side legs that are interconnected by a bridge. The bridge is essentially a small hollow tube that joins and provides internal communication between the two legs. An electrode is mounted to the end of each leg. The hollow bridge allows electricity to flow from one electrode to the other to complete the electrical path required to operate the lamp. The legs and bridge are typically integrally formed from glass, quartz or other appropriate transparent materials. In many applications, the end of the lamp containing the electrodes is mounted to a lamp base. The lamp base supports the lamp and provides an electrical plug for connecting the lamp assembly to a source of power. Typically, both legs of the lamp are glued to the base to provide a strong and durable assembly. For example, one prior art lamp assembly 200 is shown in FIGS. 1-2. The illustrated prior art lamp assembly 200 generally includes a lamp 202, a lamp base 204 and an end cap 206 (See FIG. 1). The lamp 202 includes two legs 208 and 210 that are joined by bridge 212. The electrode ends of each leg 208 and 210 are received within the lamp base 204. The lamp base 204 defines a pair of mounting holes 214 and 216 that are configured to closely receive the legs 208 and 210, respectively (See FIGS. 2A-2D). In the illustrated assembly, the legs 208 and 210 are largely circular in cross section. Similarly, the mounting holes 214 and 216 are also largely circular cross section, each having a diameter slightly larger than the outer diameter of the corresponding leg 208 and 210. FIG. 2 shows the prior art lamp assembly 200 with the end cap 206 removed. As can be seen in FIG. 2D, in one embodiment, both legs 208 and 210 are surrounded by glue 218 that secures the legs 208 and 210 to the base. The glue 218 and close interfitting relationship between the mounting holes 214 and 216 and the legs 208 and 210 essentially precludes movement of the legs 208 and 210 with respect to one another.
Experience has revealed that dual-leg lamps, although quite reliable, have been known to fail during operation as a result of fractures, cracks or other breaks in the bridge. Accordingly, there is a desire for a lamp assembly that addresses this issue.